The present invention relates to a heating device for heating a medium to be heated on moving, and in particular to a heating device adapted to be used for fusing and fixing toner on a recording sheet conveyed at an arbitrary speed in a noncontact condition within a fixing part, for example, in an electrophotographic recording apparatus, or for preheating a recording sheet in a noncontact condition before fixing.
Conventionally, for example, Japanese Laid-Open Patent No. 49-75144 discloses a heating device comprising a radiator for generating radiation energy for fusing toner on a recording sheet, and a reflector or a cover having a mirror surface covering the radiator, for preventing the radiation energy from leaking therearound.
Further, Japanese Laid-Open Patent No. 50-129038 discloses a heating device having a band-like heating element and a reflector arranged at the rear surface of the former, for heating a recording sheet over a wide range.